/Engine/Source/Runtime/Engine/Public/DerivedMeshDataTaskUtils.h
Source mesh data. Valid only in specific cases, when StaticMesh doesn't contain original data anymore (e.g. it's replaced by the Nanite coarse mesh representation)
class FSourceMeshDataForDerivedDataTask
TArray< uint32 ...
TriangleIndices
TArray< FVector...
VertexPositions